Isn't late extract addition supposed to impact color (SRM)?

According to this article, late extract addition results in paler color (lower SRM), but when I change it in BeerSmith there's no impact on color, or maybe I'm doing something wrong?

I don't think that BeerSmith, or any tool for that matter, takes into account the darkening of extract during a boil.  It definitely occurs, but is not represented in the SRM calculation. 

In short, I believe BS2 will generally tell you the SRM based on ideal conditions (e.g., no darkening whatsoever), and the assumption is that less than optimal procedures may result in a darker beer.